FR2686433A1 - Actuation device for an accelerator - Google Patents

Abstract

An actuation device (1) for an accelerator is composed of a housing; a drive part (2) composed of a reversible rotary motor (4) arranged in the housing, reduction gearing (5) intended for reducing the number of revolutions of the motor (4), and an output pulley (6) linked to the reduction gearing (5) so as to wind up or unwind a control cable (7); and a control part (3) composed of an actuation part, and of a control mechanism intended for controlling the rotation of the motor on the basis of a discrepancy between a position of the actuation part and a position of the output pulley (6), the drive part (2) and the control part (3) being linked coaxially to one another as one piece.

Description

OPERATION DEVICE FOR A

ACCELERATOR

  The present invention relates to an actuating device for an accelerator (hereinafter simply called "actuating device"), and more particularly to an actuating device intended to remotely control a speed regulator by automatically regulating a degree of opening in order to be used in a diesel engine or equivalent, for example in construction equipment The actuating device of the present invention can be used for different purposes, for example to control

a valve or a motor.

  Conventionally, equipment such as a mechanical shovel has an automatic deceleration or programmed driving function

  adapted to the necessary operations.

  As shown in FIG. 8, an actuating device 61 of a conventional type comprises a driving part 63 having an output pulley 62 and a control part 65 having a feedback pulley 64, which are provided with separately For this reason, a motor speed regulator 66 is provided with a small pulley 68 as well as a motor pulley 67 The reference 69 indicates a motor, the reference 70 indicates an actuating disc, and the reference 71 indicates a terminal plate which is connected to the actuating disc 70 The output pulley 62 and the motor pulley 67 are connected to each other by means of a control cable 72, and the feedback pulley 64 and the small pulley 68 are connected on the other hand to each other by means of a feedback cable 73 An electrode plate 74 is mounted on the feedback pulley 64, and a terminal 75 for the acceleration and a terminal 76 for deceleration s have been provided on the terminal plate 71 and are intended to come into sliding contact with the

electrode plate 74.

  With the conventional actuating device 61 thus arranged, when the actuating disc 70 is rotated so as to be adjusted by a certain angle, and if there is a deviation between the angle adjusted by the actuating disc 70 and the angle at which the feedback pulley 64 rotates in response to adjustment by the actuating disc 70, the motor 69 rotates, in response to an output signal corresponding to the deflection, in a direction which cancels the deflection The motor 69 causes the motor pulley 67 to rotate by means of the output pulley 62 and the control cable 72. When the motor pulley 67 rotates, the angle of rotation thereof is transmitted by the intermediate of the feedback cable 73 to the feedback pulley 64 Such an operation is continued until the deflection is canceled. The opening of the cruise control is thus controlled so as to adjust the speed of rotation of the motor. r to a value

possibly desired.

  As described above, the conventional actuator 61 for use in an acceleration control device has the drive portion 63 and the control portion 65 separately. Therefore, it is difficult to reduce the size of the actuating device 61, therefore the time and labor required to mount it on a machine This leads to an increase in the manufacturing cost of the

actuating device.

  The present invention was made in order to overcome these problems. It is thus an aim of the present invention to provide a device.

  simplified actuation and reduced size.

  According to the present invention, there is provided an actuating device for an accelerator comprising: (a) a housing; (b) a drive part comprising a reversible rotary motor disposed in the housing, a speed reducer intended to reduce the number of revolutions of the motor, and an output pulley connected to the speed reducer in order to wind or unwind a control cable; and (c) a control part comprising an actuation part, and a control mechanism intended to control the rotation of the motor as a function of a deviation between a position of the actuation part and a position of the output pulley. , the drive part and the control part being

  connected coaxially to each other in one piece.

  In the present invention, the drive part preferably comprises the motor, a first speed reducer connected to an output shaft of the motor, a second reducer connected to an output part of the first speed reducer, and the output pulley arranged in an exit part of the second

speed reducer.

  In this case, the second reduction gear is preferably a reduction gear with planetary gear comprising a central pinion connected to the outlet part of the first reduction gear, several satellites arranged around and engaged with the central pinion, and a pinion with internal toothing engaged circumferentially with the satellites and integrated into a lower part of the output pulley, a shaft of each of the satellites being supported at its lower end by the housing while it pivots at its upper end thanks to a bearing element; and the bearing element is free of any element that

other the satellite tree.

  On the other hand, the control part preferably comprises a plate mounted on its underside with a terminal for forward rotation of the motor and a terminal for rearward rotation of the latter, a drive shaft. actuation projecting from the plate in order to drive the plate in rotation, and an electrode plate fixed to the output shaft of the second reducer so as to face a lower face of the plate, the plate and the plate d 'electrodes being arranged in the control mechanism so as to bring the two terminals in sliding contact with the electrode plate; the output shaft of the second reducer being freely mounted in a hole formed in the center of the

underside of the plate.

  In addition, the control mechanism is preferably arranged so that a common terminal is fixed to the electrode plate so as to allow the electrode plate to be conductive via a conductive cable. and the common terminal. More preferably, the control mechanism has an insulating plate disposed on the plate, thus separating the upper compartment of the plate from the lower compartment thereof, cables respectively connecting the terminal for the forward rotation of the motor. and the terminal for the rearward rotation thereof being provided on the

insulating plate.

  In the actuating device of the present invention, when the actuating part is rotated by a certain angle corresponding to a desired speed regulator opening of a motor and there is a deviation between an angle of rotation of the output pulley and the angle adjusted by the actuating part, the control mechanism causes the motor of the driving part to rotate by a value and in a direction such that this cancels the deflection This rotation of the motor is transmitted through the reducer to rotate the output pulley The rotation of the output pulley causes the control cable to act so as to rotate the motor pulley connected to the speed regulator of the motor, thus adjusting

  opening the cruise control.

  Figure 1 is a schematic perspective view showing a motor control device provided with an actuating device implementing the present invention; Figure 2 is a perspective view showing the actuator of Figure 1 before assembly; Figure 3 is a vertical sectional view showing the actuator of Figure 1; Figure 4 is a sectional view along the line IV-IV of Figure 3; Figures 5 and 6 are each an explanatory view intended to illustrate an operation of the actuating device of Figure 1; FIG. 7 is a circuit diagram showing an embodiment of a control circuit of an actuating device according to the present invention; and Figure 8 is a schematic perspective view showing an example of a device

conventional actuation.

  The present invention will now be

  described with reference to the drawings.

  Referring to FIG. 1, an actuating device 1 comprises a driving part 2 and a control part 3 which are assembled coaxially and in one piece The driving part 2 comprises a motor 4 , a reduction part 5, and an output pulley 6 made in one piece with the reduction part 5 on the outer side thereof The output pulley 6 is connected to a motor pulley 8 via a control cable 7 (hereinafter called "cable") The rotation of the output pulley 6 causes the motor pulley 8 to rotate by means of the cable 7, so as to open or close a speed regulator 9 connected to the

motor pulley 8.

  If one refers to Figures 2 and 3 which illustrate in detail the actuating device 1, the reference 10 indicates a housing, the reference 11 indicates a motor housing, and the reference 12 indicates a cover element These three elements (the housing 10, the motor 11, and the cover 12) cooperate in order to receive the drive part 2 and the control part 3 The housing 10 is of rectangular parallelepiped shape in the upper part thereof while

  being cylindrical in the lower part.

  The drive part 2 will be described first. The reduction part 5 comprises a first reduction gear 13 of the Fergusson paradox type and a second reduction gear 14 The first reduction gear 13 comprises a central pinion 15 fixed on the motor shaft 4, two satellites 16 arranged around and engages with the pinion central 15, a pinion with fixed internal teeth 17 and a pinion with rotatable internal teeth 18, the pinions 17 and 18 facing each other and engaging the planet gear 16 The pinion with fixed internal teeth 17 is supported between the motor 4 and the housing 10, while the pinion with internal rotary teeth 18 forming the outlet part of the first reduction gear 13 is on the other hand guided in a rotary fashion along the internal periphery of the housing 10 The satellites 16 are each supported in a manner rotatable by an axis 20 extending between a pair of vertically opposite supports of substantially annular shape When the central pinion is rotated, each of the satellites 16 rotates around its axis while turning around the central pinion 15 with the supports 19 The pinions with internal teeth 17 and 18 differ slightly from each other in terms of the number of teeth The rotation of the motor 4 is therefore greatly reduced by the pinion toothing

  internal rotary 18 and used at output.

  The second reduction gear 14 comprises: a central pinion 22 formed on a first shaft 21 which protrudes in the center of the pinion with internal rotary teeth 18; three satellites 23 arranged around and engaged with the central pinion 22; and a pinion with internal teeth 24 which is engaged with the planets 23 The planes 23 are arranged on the upper face of an annular separation plate 25 formed on an internal periphery of the housing 10 so as to be directed towards a center ( an imaginary axis) of the thrust shaft 21 An annular bearing 27 has three axes 26 protruding therefrom in a manner corresponding to the satellites 23 and fitting into the central bores of the respective satellites 23, and each axis 26 is inserted into respective bearing holes 28 formed in the separation plate 25 Because the three planets 23 are carried by the single removable bearing 27, that is to say a "floating bearing", the outlet part of the second reducer formed integrally with the pinion with internal teeth 24 can be easily assembled with the

satellites 23.

  The internal gear 24 is formed integrally with the output pulley 6 at an upper part thereof. More specifically, a fixing hole 29 intended to fix one end of the cable 7 is formed in the upper face of the pinion with internal teeth 24, while a groove 30, which communicates with the fixing hole 29 which is intended to wind the cable 7, is formed in the outer peripheral face thereof A stepped shaft 31 having different diameters protrude from the center of the upper face of the output pulley 6 and journals in a bearing bore 33 of a guide plate 32 fixed inside the housing 10 The upper face of the output pulley 6 is also produced with a projection 34 which is designed to be housed freely in a guide groove 35 formed in the guide plate 32 in order to limit an angle of

rotation of the output pulley 6.

  The control part 3 will be described in turn. The upper part of the stepped shaft 31 which projects upwards from the guide plate 32 is fixed in a circular electrode plate 36 On the upper face of the electrode plate 36 is formed an electrically conductive part 37 composed of a sector-shaped part whose central angle is slightly less than 1800 and of a peripheral part which is independent of the sector-shaped part The electrode plate 36 is pinned at a point spaced from its center on the projection 34 The output pulley 6 and the electrode plate 36 are thus provided to rotate together A common terminal 38 inserted in and fixed to the projection 34 is brought into direct contact with the electrically conductive part 37 of the electrode plate 36 without using a brush Because the current flows directly to the electrically conductive part 37 by means of a conductive wire, the structure of the

  control part 3 is simplified.

  A mobile terminal plate 39 is rotatably disposed on the upper face of the electrode plate 36 The mobile terminal plate 39 comprises a substantially circular plate 40 and an actuation shaft 41 projecting from the upper face of the plate 40 In the lower face thereof is formed a mounting hole 42 coaxial with the actuating shaft 41 in which is housed so

  rotating the upper end of the stepped shaft 31.

  On the other hand, the actuation shaft 41 protrudes towards the outside of the cover 12 through a hole 43 formed in the cover 12 and is designed to be mounted with an actuation disc 44 on the underside of the plate 40 are fixed a brush 45 for the forward rotation of the motor 4 (hereinafter called "front terminal") and a brush 46 for the rearward rotation of the latter (hereinafter called "rear terminal") ) which come in sliding contact with the plate

  of electrodes 36 Opposite the semi-plate

  circular 40 and slightly spaced therefrom by the actuating shaft 41 is provided a plate 47 for a self-deceleration terminal (hereinafter called "deceleration terminal plate") which is fixed inside the housing 10 and fixed with a brush for self-deceleration (hereinafter called "self-deceleration terminal") Just like terminals 45 and 46, the self-deceleration terminal 48 comes into sliding contact with the plate of electrodes 36 An insulating plate of circular shape 49 extending above the deceleration terminal plate 47 is mounted on the upper face of the plate 40 This insulating plate 49 serves to prevent the wires in an upper space 50 d '' enter a lower space 51 in order to come into contact with and wind around the output pulley 6, slow down the rotation of the latter or drive

  a short circuit with the electrode plate 36.

  The operation of the actuation device 1 thus constructed will be described in

referring to Figures 4 to 6.

  FIG. 4 illustrates a relative position relation between the electrode plate 36,  the semicircular plate 40 of the movable terminal plate 39 and the deceleration terminal plate 47 A contact point 45 a of the front terminal 45 and a contact point 46 a of the rear terminal 46 are positioned on an imaginary line passing through the center of the plate 40 so that the center is interposed between the contact points 45 a and 46 a of the electrode plate 36 On the other hand,  the electrically conductive part 37 of the electrode plate 36 has a sector part, the central angle of which is slightly less than 1800 as has been described above.  the contact points 45 a and 46 a are both positioned slightly away from the electrically conductive part 37 When the actuating shaft 41 is rotated with the actuating disc 44,  the plate 40 which is made in one piece with the actuating shaft 41 is also rotated so that the front terminal 45 and the rear terminal 46 rotate together For example,  the rotation of the actuation shaft 41 in the direction of arrow A causes the two terminals 45 and 46 to move towards the respective positions shown in FIG. 5 so that the contact point 45 a of the front terminal 45 comes into contact with the electrically conductive part 37 The motor 4 in the drive part 2 then rotates in the forward direction,  which causes the output pulley 6 to turn in a direction such that it pulls the cable 7 with the reduction part 5 An opening of the speed regulator 9 is thus controlled so that a lot of fuel can flow into the engine,  with therefore an increase in the speed of rotation of the motor. The electrode plate 36 fixed on the output pulley 6 is then rotated with the output pulley 6 in the direction of arrow A Consequently,  the rotation of the electrode plate 36 over a certain angle causes the contact point 45 a of the front terminal 45 to move away from the electrically conductive part 37,  thus stopping the motor 4 (see FIG. 6) That is to say that the relation of relative position between the electrically conductive part 37 and the two terminals 45 and 46 happens to assume the same state as the initial state (see Figure 4).  In other words, as is clear from FIGS. 4 to 6, the output pulley 6 is caused to rotate at an angle substantially equal to the angle of rotation of the actuating disc 44 It is obvious that the rotation of the actuation shaft 41 in the direction of arrow B in FIG. 4 causes the two terminals 45 and 46 to rotate in direction B in the same manner as above. In cooperation with this, the output pulley 6 and the electrically conductive part 37 rotate in direction B, the opening of the speed regulator 9 thus being reduced correspondingly to the angle of rotation of the actuating shaft 41 so that the number of revolutions of the motor is brought to decrease The opening of cruise control 9 is thus adjusted with the

actuating disc 44.

  An automatic deceleration mode will

then be described.

  If an operator temporarily leaves his seat while his machine is driven in the normal driving mode, the machine is brought into an automatic deceleration mode (or standby mode: approximately 1500 revolutions per minute) by pushing a button. self-deceleration D (see FIG. 7) which will be described later Although the electrically conductive part 37 is brought into contact with a contact point 48 a of the deceleration terminal 48 in FIG. 6, the circuit of the terminal deceleration 48 is usually open The circuit of the deceleration terminal 48 is then closed by actuating the auto-deceleration button Consequently, the automatically decelerated pipe is produced only when the peripheral part of the electrically conductive part 37 is in contact with the contact point 48 a of the deceleration terminal 48 as shown in FIG. 6, where the circuit is closed In other words mes, if the angle on which the output pulley 6 rotates is greater than the predetermined angle for which the contact point of the deceleration terminal 48 is positioned, or if the opening of the speed regulator is actually greater than that of the cruise control which is set to the value of the automatic deceleration mode, an electrical conduction occurs between the deceleration terminal 48 and the electrically conductive part 37 in order to turn the motor 4 Then, when the electrode plate 36 rotates in the direction of arrow C in FIG. 6 and that the contact point 48 has come out of the electrically conductive part 37, the motor 4 is caused to stop The speed of rotation of the motor in the automatic deceleration mode ( for example around 1500 revolutions per minute) is determined as a function of the speed regulator opening which corresponds to the position of the deceleration terminal 48 during this stop of the motor 4 Because the angle of rotation of the actuating disc 44 is not modified in the automatic deceleration mode, if the operator presses the auto-deceleration button D again in order to return to the mode normal driving, the motor 4 rotates forward so that the output pulley 6 rotates so as to open the cruise control 9 until the initial cruise control opening is found. The on / off control of the motor 4 described above can be achieved by means of an electrical circuit, for example as shown in FIG. 7 In FIG. 7, an acceleration contactor Sa is made up of the part electrically conductive 37 and the contact point a of the front terminal 45 shown in FIGS. 4 to 6 and is closed when the angle of rotation of the actuating disc 44 becomes greater than that of the output pulley 6, whereas, on the other hand, a deceleration switch Sb consists of the electrically conductive part 37 and the contact point 46 a of the rear terminal 46 shown in Figures 4 to 6 and is closed when the angle of rotation of the disc actuation 44 becomes weaker than that of the output pulley 6 A self-deceleration contactor Sd is closed when the angle of rotation of the output pulley 6 is greater than the predetermined angle at which the contact point 4 8 a of the deceleration terminal 48 is positioned, while it is open when it is the same or when it is less than the predetermined angle, without depending on the angle of

  rotation of the actuating disc 44 The auto button

  deceleration D is a switch, pressing it for the first time bringing the contact into a first contact point, while pressing it again brings the contact into a second

point-of-contact.

  In addition, in FIG. 7, contact points KI and K 2 of two relays Ri and R 2 are provided between the motor 4 and a DC power source P When a coil Cl of the relay RI is energized, the motor 4 rotates forwards, whereas, on the contrary, when the relay R 2 drives, the motor rotates towards the rear When the two contact points Ki and K 2 are open, a dynamic braking effect short- circuit acts so that motor 4 does not turn even if the two relays RI and R 2 are incorrectly energized The acceleration switch Sa and a first contact point Dl of the auto-deceleration button D are connected in series and inserted between the coil Ci of the first relay RI and the DC power source P On the other hand, the deceleration contactor Sb is inserted between the coil C 2 of the second relay R 2 and the power source direct current P In addition, the auto-deceleration switch Sd and l e second contact point D 2 of the auto-deceleration button D are connected in series and further connected in parallel to the

deceleration switch Sb.

  In the above circuit arrangement, when the self-deceleration button D is not pressed, the closing of the acceleration contactor Sa causes the first relay Rl to work so as to rotate the motor 4 forwards , thus increasing the speed of rotation of the motor, while on the other hand, the opening of the latter causes the increased speed of rotation to be maintained In turn, the closing of the deceleration contactor Sb brings about the second relay R 2 to operate in such a way as to rotate the motor 4 towards the rear, thus reducing the speed of rotation of the motor, while on the other hand, the opening of the latter brings about the speed of rotation

reduced to be maintained.

  When the auto-deceleration button D is pressed, the first contact point Dl connected in series to the acceleration switch Sa is open so as to cause the motor 4 to turn backwards until the switch d auto-deceleration Sd is open, regardless of the state of the acceleration contactor Sa and that of the deceleration contactor Sb If the self-deceleration contactor Sd is open, the auto-decelerated speed of the motor is

  In turn, when the auto button

  deceleration D is pressed again, the second contact point D 2 is open while the first contact point Dl closes, thus returning to the

normal driving mode.

  As described above, the present actuation device can be controlled mechanically by using practically no electronic circuit. As has been described, the actuating device of the present invention is arranged so that the drive part and the control part thereof are integrated coaxially with each other, and can be mechanically controlled without using a complicated electronic circuit The present actuation device therefore becomes compact and simpler, which contributes to a great reduction in the manufacturing cost In addition, the present actuation device can be very easily mounted on a machine with simplified maintenance. Although various embodiments of the present invention have been described above, it is obvious that changes and modifications can be made to the invention without departing from

  the spirit and scope of it.

Claims (5)

CLAIMS.   1 actuating device (1) for an accelerator, characterized in that it comprises: (a) a housing (10); (b) a drive part (2) comprising a reversible rotary motor (4) disposed in the housing (10), a speed reducer (5) intended to reduce the number of revolutions of the motor, and an output pulley ( 6) connected to the speed reducer (5) in order to wind or unwind a control cable (7); and (c) a control part (3) comprising an actuation part, and a control mechanism intended to control the rotation of the motor (4) according to a deviation between a position of the actuation part and a position of the output pulley (6), the drive part (2) and the control part (3) being coaxially connected to each other the other in one piece.   2 actuating device (1) according to claim 1, characterized in that the drive part (2) comprises the motor (4), a first speed reducer (13) connected to an output shaft of the motor (4 ), a second speed reducer (14) connected to an output part of the first speed reducer (13), and the output pulley (6) arranged in a   output part of the second speed reducer (14).   3 actuating device (1) according to claim 2, characterized in that the second reducer (14) is a planetary gear reducer comprising a central pinion (22) connected to the outlet part of the first reducer (13), several satellites (23) arranged around and engaged with the central pinion (22), and a pinion with internal teeth (24) circumferentially engaged with the satellites (23) and integrated into a lower part of the output pulley (6), a shaft (26) of each of the satellites (23) being supported at its lower end by the housing (10) while it pivots at its upper end by means of a bearing element (27); and the bearing element (27) is free from   any element other than the tree (26) of the satellite (23).   4 actuating device (1) according to claim 1, characterized in that the control part (3) preferably comprises a plate (40) mounted on its underside with a terminal (45) for rotation forward of the motor (4) and a terminal (46) for a rearward rotation thereof, an actuating shaft (41) projecting from the plate (40) in order to drive the plate (40) in rotation, and an electrode plate (36) fixed on the output shaft (31) of the second reduction gear (14) so as to face a lower face of the plate (40), the plate (40) and the plate d 'electrodes (36) being arranged in the control mechanism so as to bring the two terminals (45, 46) in sliding contact with the electrode plate (36); the output shaft (31) of the second reduction gear (14) being freely mounted in a hole (42) formed   in the center of the underside of the plate (40).   Actuation device (1) according to claim 4, characterized in that the control mechanism is arranged so that a common terminal (38) is fixed to the electrode plate (36) so as to allow the electrode plate (36) to be conductive via a conductive cable and the common terminal (38).   6 actuating device (1) according to claim 4, characterized in that the control mechanism has an insulating plate (49) disposed on the plate (40), thus separating the upper compartment (50) from the plate (40) the lower compartment (51) thereof, cables respectively connecting the terminal (45) for the forward rotation of the motor and the terminal (46) for the rearward rotation of the latter being provided on plate insulating (49).